Why six years is a hard number, not a soft one

Montana treats construction repose as substantive immunity rather than a procedural deadline. In Atkinson v. City of Livingston, 2026 MT 21, decided February 10, 2026, the Supreme Court described § 27-2-208 as “a substantive grant of immunity that extinguishes liability once the repose period expires,” citing among other authority Association of Unit Owners of Deer Lodge Condominium v. Big Sky of Montana, Inc., 245 Mont. 64, 798 P.2d 1018 (1990).⁴

The same opinion closed the re-pleading route. The court looks to “the gravamen of the claim rather than the label attached”: “Claims styled as negligence and negligent misrepresentation do not avoid the repose when they arise out of construction-related governmental functions.” Atkinson applied the ten-year version, because the suit was filed in April 2024. Associations filing after October 1, 2025 face the six-year version and the same doctrine.

The condominium transition problem this creates

Association defect claims surface late by nature. Turnover from a declarant happens after completion; envelope, roof and drainage failures manifest later still; and a volunteer board often needs a full budget cycle to get an engineer's report in hand. Six years from substantial completion is a short runway for that sequence, and the earlier trigger — completion certificate or first beneficial use, whichever is earlier — can pull the start date back further than a board expects.

Practical consequence for a Montana condominium or townhome association:

• Find the completion date before you need it. Not the closing date, not the recording date — the certificate or first beneficial use. That date is the only one the statute cares about.
• Buildings completed in 2020 or 2021 are at or past the new outer limit. An association still weighing whether to pursue a known defect on those buildings is weighing a decision the statute may already have made.
• Move the transition audit earlier. A reserve study tells you what things cost; a transition or building-envelope review tells you whether anyone else is liable for them. The second one now has a deadline.

The second clock: covenant abandonment came in two years sooner

This is the connection that is easy to miss, because it runs through a cross-reference. § 70-17-210(2) ties the covenant-abandonment defence to “the prescribed period in 27-2-202” — the very subsection SB 143 cut from eight years to six.

So a Montana covenant now goes dormant two years earlier than it did before October 1, 2025. Pair that with House Bill 147, effective May 5, 2025, which defines “enforcement action” as enforcement “equally and consistently” applied “on all properties subject to the covenant over at least a 2-year period,” and the two 2025 changes point the same way: the standard for preserving a covenant went up while the window for losing it got shorter.

The same six-year period applies, on the face of the statute, to actions on the declaration itself and to written assessment obligations.

What is genuinely unsettled

SB 143's applicability section (Sec. 3) says the act applies to actions “on any contract, covenant, obligation, or liability founded on an instrument in writing that are filed on or after October 1, 2025.” That sentence speaks to written-instrument actions. Whether the shortened construction repose in § 27-2-208 reaches claims that accrued before October 1, 2025 is not resolved by the statute's text, and we found no Montana decision construing it. Treat that as an open question rather than an answer in either direction — and treat it as a reason to establish your completion dates now instead of assuming which version applies.